• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.788-795
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• 2005

In this study, the progressive failure and creep of the traditional ground anchor structure were decreased and a new ground anchor that can attain the required pull-out resistance even in soft sandy soils with low confining pressure was developed. Ground anchors are classified depending on the kind of stress the grout is subjected. If the grout material is subjected to tension then it is classified as tension anchor while when the grout material is subjected to compression it is classified as compression anchor. The ground anchor that possesses both the tension and compression mechanism mentioned above is known as composition anchor. It is the objective of this study to develope this type of composition anchor. The structure of the newly developed ground anchor was presented. Pull-out test in different types of soil and the behaviour during Pull-out test was also presented.

• 수산해양기술연구
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• 제59권2호
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• pp.110-116
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• 2023

In this study, samples of sea anchor canopy cloth mainly used in Korean jigging fishing vessels were collected and tested for performance evaluation. The canopy cloth of sea anchor is a basic element of form composition that is known to have the greatest influence on anchor performance. In order to evaluate the performance of sea anchor canopy cloth, five types of samples were tested for new metric count, tensile strength, water vapour transmission rate and drying speed according to the national standard (KS), and some correlations were identified. As a result of the test, the new metric count of cloths was 335.5-443.4 denier in warp and 217-447.6 denier in weft, and the minimum tensile strength was 860 N in warp direction and 430 N in weft direction. The apparent number and tensile strength of cloth were proportional, the water vapour transmission rate of the sample was 206.8 g/m²h, and the drying speed was 90-100 min. This study partially confirmed the performance evaluation based on speculation by the standard test method, and further research is needed on the clear relationship between the research results and the performance of the sea anchor.

• 수산해양기술연구
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• 제58권4호
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• pp.289-298
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• 2022

Sea anchor for fishery is commonly used in jigging fishery and purse seine. The study of sea anchor was studied for improvement of opening efficiency and drag by changing the type of shape and the diameter of vent. However, standard specification of sea anchor is not set and has not been studied for underwater stability. Therefore, this study aimed to improve underwater stability of sea anchor by changing a vent diameter and weight of sinker. The experiment was conducted in flume water tank. The experiment model of sea anchor was made from actual model of sea anchor which is used in fishery by similarity law. The model of sea anchor was designed to different types of vent diameter and weight of sinker in different current speed. The value of movement of side to side (X-axis), drag of sea anchor (Y-axis) and movement of up and down (Z-axis) was measured for 30 seconds. Each value of X, Y, Z-axis was analyzed through t-test and ANOVA analysis to verify that each value had a significant difference according to the difference compositions. There was correlation between the movement of X-axis and Z-axis. The drag of sea anchor was stronger as the current speed increased. However, the larger the vent diameter, the weaker the drag. From the result of the standard deviation, the movement of X-axis was inversely proportional to the vent diameter. However, movement of Z-axis was larger as the weight of sinker was the heaviest or lightest from the result of the standard deviation. These results suggest that the sea anchor should be combined with proper size of the vent diameter and the weight of sinker to improve the stability.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.1229-1234
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• 2005

Since the 20th century, the business of railway was invaded by the invention of airplanes and vehicles in the field of the transportation of passenger and commercial products, however, in the 21st century, the fervent development of a high speed railway made possible the huge capacity of transporting passengers and commercial freight, so the railway industry is facing a new era of railway revolution. The 200 years old railway tradition includes the history of railway bridges built in areas of river, valley and metropolitan region and in that, the number of constructions of railway bridges that is composed of cable-stayed bridges is increasing as one of the most optimal bridges considering the quality of materials and the span of continuous-welded long rail. Thanks to the minimized effects of the fixed load on the stiffening girder section by delivering the fixed load which is applied to the pylon with the composition of elastic supporting points by using cables and the effective structural system that can throughly resist extra loads in addition to fixed load, the long-extended span of a bridge becomes possible. In this structural system, the load that is applied to the stiffening girder section forms a now pattern and in the process of these load delivery, there will be a necessity to examine the concentration of stress occurred in the cable-anchor system of the cable.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.552-557
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• 2006

Since the 20th century, the business of railway was invaded by the invention of airplanes and vehicles in the field of the transportation of passenger and commercial products, however, in the 21st century, the fervent development of a high-speed railway made possible the huge capacity of transporting passengers and commercial freight, so the railway industry is facing a new era of railway revolution. The 200 years old railway tradition includes the history of railway bridges built in areas of river, valley and metropolitan region and in that, the number of constructions of railway bridges that is composed of cable-stayed bridges is increasing as one of the most optimal bridges considering the quality of materials and the span of continuous-welded long rail. Thanks to the minimized effects of the fixed load on the stiffening girder section by delivering the fixed load which is applied to the pylon with the composition of elastic supporting-points by using cables and the effective structural system that can throughly resist extra loads in addition to fixed load, the long-extended span of a bridge becomes possible. In this structural system, the load that is applied to the stiffening girder section forms a flow pattern and in the process of these load delivery, there will be a necessity to examine the concentration of stress occurred in the cable-anchor system of the cable.

• Journal of Ecology and Environment
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• 제30권3호
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• pp.209-223
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• 2007

Twenty-four wetlands located in Higashi-Hiroshima City in West Japan were selected for this study in order to investigate both the relationship between aquatic plant composition and environmental conditions; and the relationship between changing land use patterns in the catchments and the concentration of different forms of nitrogen in the wetlands. The dominant and subdominant species which comprised the principal vegetation were determined based on a vegetation census conducted in each wetland during the growing season from June to August, 2006. The seasonal variations of water quality factors (pH, electrical conductivity, turbidity, dissolved oxygen, total dissolved solid, and temperature) and different forms of nitrogen such as nitrite, nitrate, ammonium, total nitrogen, dissolved organic nitrogen and dissolved inorganic nitrogen concentrations were analyzed as important indicators of water quality for the surface water of the wetlands. The surveyed wetlands were classified into three types (non-disturbed wetlands, moderately-disturbed wetlands and highly-disturbed wetlands), based on the degree of human disturbance to their catchment areas. An analysis of variance indicated that there was a significant difference among the wetland groups in the annual mean values of electrical conductivity, total dissolved solids, total nitrogen, nitrite, dissolved inorganic nitrogen and dissolved organic nitrogen. Classification of the wetlands into three groups has revealed a pattern of changes in the composition of plant species in the wetlands and a pattern of changes in nitrogen concentrations. A majority of the non-disturbed wetlands were characterized by Brasenia schrebi and Trapa bispinosa as dominant; with Potamogeton fryeri and Iris pesudacorus as sub-dominant species. For most of the moderately-disturbed wetlands, Brasenia schrebi were shown to be a dominant species; Elocheriss kuriguwai and Phragmites australis were observed as sub-dominant species. For a majority of the highly-disturbed wetlands, Typha latifolia and T. angustifolia were observed as dominant species, and Nymphea tetragona as the sub-dominant species in the study area. An analysis of land use and water quality factors indicated that forest area played a considerable role in reducing the concentration of nutrients, and can act as a sink for surface/subsurface nutrient inputs flowing into wetland water, anchor the soil, and lower erosion rates into wetlands.

• 폴리머
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• 제36권1호
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• pp.104-110
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• 2012

LCD 컬러필터에서 안료의 분산은 컬러 강도를 증가시키는 중요한 요소이므로, 안료를 분산시키기 위한 안료 분산제의 첨가는 필수적이라 할 수 있다. 안료 분산제로서의 고분자는 안료와의 친화성을 가지는 anchoring group과 매체와의 혼화성을 가지는 stabilizing group을 포함하고 있다. 원자 이동 라디칼 중합은 잘 규정된 고분자 합성을 가능하게 하는 중합법으로, 이러한 구조를 포함하는 고분자형 안료 분산제를 얻기 위한 적절한 수단이 될 수 있다. Anchor로서 (2-dimethylamino)ethyl methacrylate를, stabilizer로서 oligo(ethylene oxide)methyl ether methacrylate를 각각 선택해 고분자 분산제를 합성하였다. 고분자의 구조 및 조성이 안료 분산에 미치는 영향을 연구하기 위해 다양한 길이의 stabilizing group을 가지는 diblock copolymer를 합성하여 비교하였다.

• 한국수산과학회지
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• 제31권2호
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• pp.195-201
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• 1998

멸치젓 숙성 중 지질의 산화가 멸치젓의 품질에 미치는 영향을 검토코자 멸치에 대하여 식염을 $10\%$와 $20\%$ (w/w)로 혼합한 다음, 각각 $10^{\circ}C$와 $20^{\circ}C$에서 105일간 숙성시키면서 POV와 TBA 값 및 지질함량과 지방산 조성의 변화를 비교 분석하였다. POV와 TBA 값에 비추어 숙성초기에는 식염농도 $10\%,\;10^{\circ}C$ 숙성멸치젓이 식염농도 $20\%,\;20^{\circ}C$ 숙성멸치젓보다 산화가 빠르게 진행되었다. 숙성과정중 TL함량은 $10\%$ 멸치젓에서 약 $16\%,\;20\%$ 멸치젓에서 약 $33\%$ 감소하였고, 전자에서는 TL중 주로 PL이 감소하였으나, 후자에서는 PL 및 NL이 거의 등량으로 감소하였다. 주요지방산, 즉 14 : 0, 16 : 0, 16 : In-7, 18 : In-9, 20 : 5n-3, 22 : 6n-3 함량은 생시료에 비하여, 숙성 105일째 $10\%$ 멸치젓에서는 평균 약 $81\%$의 잔존율을, $20\%$ 멸치젓에서는 평균 약 $67\%$의 잔존율을 나타냈다.

• 한국수산과학회지
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• 제30권5호
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• pp.842-849
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• 1997

Pepsin, trypsin, $\alpha-chymotrypsin$, papain, bromelain, 복합효소, Novozym 89, Neutrase 0.51., Protamex 및 Alcalase 0.6L 등으로 가수분해하여 얻은 멸치육 단백질 효소 가수분해물의 항산화작용을 살펴본 결과, 항산화작용이 매우 우수한 것으로 나타났으며 특히 생체내 소화효소의 하나인 pepsin과 식품가공용 단백분해효소인 Protamex에 의한 가수분해물의 항산화작용이 우수한 것으로 나타났다. 이들의 다른 항산화제와의 상승작용에 있어서는 $\alpha-tocopherol$과는 상승작용이 있는 것으로 나타났으나 BHT에 대해서는 BHT 자체의 강한 항산화능으로 상승작용을 확인할 수 없었다. 금속이온 $(Fe^{3+},\;Cu^{2+})$에 대한 봉쇄작용 또한 우수한 것으로 나타났으며, 특히 pepsin, $\alpha-chymotrypsin$ 및 papain유래 가수분해물이 $Cu^{2+}$이온에 대하여 높은 억제작용을 나타내었다. Pepsin유래 멸치육 단백질 효소가수분해물을 이온교환크로마토그래피 및 겔 크로마토그래피에 의하여 분획하고 얻어진 획분별 항산화작용은 P-2 (fraction No. $26\~31$)획분에서 가장 큰 것으로 나타났다. 이 때 가수분해전후 및 활성획분의 아미노산조성은 aspartic acid와 glutamic acid가 증가한 반면 alanine, cysteine, tyrosine 및 phenylalanine은 감소한 것으로 나타났다.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2008년도 제33회 펄프종이기술 국제세미나
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• pp.47-70
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• 2008

Cost efficiency is today the primary requirement in the paper and board industry. This has led therefore, to a greater preponderance of products with specifically designed functionality to take account of current industry needs. Continually increasing machine coating speeds together with these new coating colour components have put more emphasis on the importance of the correct rheology and water retention of the coating colours to achieve good runnability and end product quality. In the coating process, some penetration of the aqueous phase, to the base paper or board must occur to anchor the pre-coating to the base or the topcoat to the pre-coat. The aqueous phase acts as a vehicle not only for the binder, but also for the other components. If this water or material penetration is not controlled, there will be excessive material shift from the coating colour to the base, before immobilization of the coating colour will stop this migration. This can result in poor machine runnability, unstable system and uneven coating layer, impacting print quality. The performance of rheology modifiers or thickeners on the coating color have tended to be evaluated by the term, "water retention". This simple term is not sufficient to explain their performance changes during coating. In this paper we are introducing a new concept of "material retention", which takes note of the total composition of the coating colour material and therefore goes beyond the concept of only water retention. Controlled material retention leads to a more uniform z-directional distribution of coating colour components. The changes that can be made to z-directional uniformity will have positive effects on print quality as measured by surface strength, ink setting properties, print gloss, mottling tendency. Optical properties, such as light scattering, whiteness and light fastness delivery should also be improved. Additionally, controlled material retention minimizes changes to the coating colour with time in re-circulation giving less fluctuation in quality in the machine direction since it more closely resembles fresh coating for longer periods. Use of the material retention concept enables paper and board producers to have more stable runnability (i.e. lower process costs), improved end product quality (i.e. better performance of used chemicals) and/or optimized use of coating colour components (i.e. lower total formulation cost)